title: Menadione (vitamin K3) is a catabolic product of oral phylloquinone (vitamin K1) in the intestine and a circulating precursor of tissue menaquinone-4 (vitamin K2) in rats.
abstract: Mice have the ability to convert dietary phylloquinone (vitamin K1) into menaquinone-4 (vitamin K2) and store the latter in tissues. A prenyltransferase enzyme, UbiA prenyltransferase domain-containing 1 (UBIAD1), is involved in this conversion. There is evidence that UBIAD1 has a weak side chain cleavage activity for phylloquinone but a strong prenylation activity for menadione (vitamin K3), which has long been postulated as an intermediate in this conversion. Further evidence indicates that when intravenously administered in mice phylloquinone can enter into tissues but is not converted further to menaquinone-4. These findings raise the question whether phylloquinone is absorbed and delivered to tissues in its original form and converted to menaquinone-4 or whether it is converted to menadione in the intestine followed by delivery of menadione to tissues and subsequent conversion to menaquinone-4. To answer this question, we conducted cannulation experiments using stable isotope tracer technology in rats. We confirmed that the second pathway is correct on the basis of structural assignments and measurements of phylloquinone-derived menadione using high resolution MS analysis and a bioassay using recombinant UBIAD1 protein. Furthermore, high resolution MS and (1)H NMR analyses of the product generated from the incubation of menadione with recombinant UBIAD1 revealed that the hydroquinone, but not the quinone form of menadione, was an intermediate of the conversion. Taken together, these results provide unequivocal evidence that menadione is a catabolic product of oral phylloquinone and a major source of tissue menaquinone-4.
authors.affiliation: From the Departments of Hygienic Sciences and.
authors.forename: Yoshihisa
authors.initials: Y
authors.lastname: Hirota
authors.forename: Naoko
authors.initials: N
authors.lastname: Tsugawa
authors.forename: Kimie
authors.initials: K
authors.lastname: Nakagawa
authors.forename: Yoshitomo
authors.initials: Y
authors.lastname: Suhara
authors.forename: Kiyoshi
authors.initials: K
authors.lastname: Tanaka
authors.forename: Yuri
authors.initials: Y
authors.lastname: Uchino
authors.forename: Atsuko
authors.initials: A
authors.lastname: Takeuchi
authors.forename: Natsumi
authors.initials: N
authors.lastname: Sawada
authors.forename: Maya
authors.initials: M
authors.lastname: Kamao
authors.forename: Akimori
authors.initials: A
authors.lastname: Wada
authors.forename: Takashi
authors.initials: T
authors.lastname: Okitsu
authors.forename: Toshio
authors.initials: T
authors.lastname: Okano
mesh_terms: D000818:Animals; D004122:Dimethylallyltranstransferase / Q000235:genetics / Q000378:metabolism; D005260:Female; D007413:Intestinal Mucosa / Q000378:metabolism*; D008297:Male; D051379:Mice; D051381:Rats; D017207:Rats, Sprague-Dawley; D011994:Recombinant Proteins / Q000235:genetics / Q000378:metabolism; D013045:Species Specificity; D010837:Vitamin K 1 / Q000493:pharmacokinetics* / Q000494:pharmacology; D024482:Vitamin K 2 / Q000031:analogs & derivatives* / Q000378:metabolism; D024483:Vitamin K 3 / Q000378:metabolism*; D014815:Vitamins / Q000493:pharmacokinetics* / Q000494:pharmacology
chemical_list: D011994:Recombinant Proteins; D014815:Vitamins; D024482:Vitamin K 2; C030814:menatetrenone; D024483:Vitamin K 3; D010837:Vitamin K 1; D004122:Dimethylallyltranstransferase
keywords: Conversion; Enzymes; Intestine; Menadione; Menaquinone-4; Metabolism; Phylloquinone; Rat; UBIAD1; Vitamin K